White Paper · Business & Contracts · Healthcare Formation

Choosing the Entity: PC, PLLC, and the MSO Model in Illinois

For an Illinois professional practice, entity choice is not a tax-label exercise. Licensing, ownership, management, professional-fee rules, payer enrollment, contracts, and any management-company structure have to fit together before the first patient or client is served.

By Lincoln Square Law · 8-minute read

Start with the professional service, not the tax election

Entity planning should begin with what professional service the business will render and which Illinois license governs it. A general LLC can be formed for many lawful purposes, but section 1-25 of the Illinois LLC Act says an LLC intending to provide a professional service licensed by the Department of Financial and Professional Regulation must comply with the Professional Limited Liability Company Act. The professional-entity statutes then add ownership and service-specific requirements.

Tax treatment is a separate layer. An entity’s federal tax election does not by itself determine whether the entity is authorized to render a licensed service in Illinois. Counsel should first select a legally eligible entity and ownership structure, then coordinate tax elections with the accountant. Reversing that order can produce a company that has the desired tax profile but the wrong professional ownership or licensure architecture.

Professional corporations have licensed-owner constraints

The Professional Service Corporation Act allows licensed individuals to organize a professional corporation to render the same or related professional services. The Act’s definition of a professional corporation generally limits shareholders, directors, officers, agents, and professional employees to appropriately licensed individuals, subject to statutory details and exceptions. Formation documents also identify the profession to be practiced.

For a healthcare practice, that means the cap table cannot be treated like an ordinary startup cap table. Before issuing shares, options, or other ownership interests, confirm that the proposed holder is eligible under the governing professional statute and the specific licensing law. Build transfer restrictions into the governing documents so an otherwise routine estate, divorce, financing, or investment transaction does not create an impermissible owner.

The PLLC statute creates a parallel professional form

Illinois also authorizes professional limited liability companies. The PLLC Act is designed for licensed professionals to render professional services while using an LLC form. Section 13 contains service-specific rules, including requirements for medicine and dentistry. For medicine, the statute addresses who may be members and requires managers, if any, to be licensed to practice medicine, subject to the statutory categories of permitted members.

The PLLC form can offer governance flexibility, but “LLC flexibility” does not erase professional restrictions. The operating agreement should track the licensing requirements, admission eligibility, loss-of-license consequences, transfer limits, and management authority. If a professional entity will own another professional entity, confirm that the ownership chain is permitted rather than assuming entity-to-entity ownership is universally allowed.

Medicine adds fee-splitting and ownership rules

Section 22.2 of the Medical Practice Act prohibits physicians from dividing or sharing professional fees in exchange for referrals or otherwise except as allowed by the statute. The section also identifies entities through which physicians may practice and includes ownership requirements and other exceptions. The statute was amended in 2026, so current structuring should use the operative text and source notes rather than an older summary of Illinois corporate-practice doctrine.

This is central to management-company design. A management fee that is expressed as a percentage of professional revenue may create issues distinct from a fixed or fair-market-value management charge, depending on the arrangement and statutory exception. Do not start from a preferred economics model and attempt to force it into the professional practice. Start from the professional-entity and fee rules, then design compensation for legitimate management services around them.

An MSO does not become the clinical practice

A management services organization can provide nonclinical functions such as billing support, technology, human resources, facilities, procurement, marketing support, or administrative infrastructure. But the professional entity should retain the clinical and professional functions that law and licensure require it to control. Agreements should identify who hires or supervises licensed clinicians, establishes clinical policy, controls professional judgment, owns patient records where applicable, and makes decisions that cannot be delegated to an unlicensed manager.

Avoid contractual control rights that make the management company the professional practice in substance. Broad vetoes over hiring licensed professionals, clinical protocols, referrals, or professional-fee decisions can undermine the intended separation. The MSO can have strong protections for its legitimate economic interests, including budgets, service standards, payment, data security, and facilities, without taking control of professional judgment.

Build the ownership chain on paper before filing

Create an ownership-and-control diagram showing every entity, owner, manager, director, and key contract. Mark which persons are professionally licensed and which entity bills for professional services. If a holding company or MSO sits above or beside the practice, show the exact ownership relationship rather than using “affiliated” as a substitute for analysis. Then compare that diagram to the Professional Service Corporation Act, PLLC Act, Medical Practice Act, and any profession-specific statute.

The diagram should also identify intellectual property, equipment, leasehold interests, employees, vendor contracts, and debt. Many problems arise because assets are placed in one entity while a contract assumes another entity owns them.

Entity choice is only useful when the documents and operations respect the boundaries the structure creates.

Coordinate entity choice with payer and licensing enrollment

A legally valid company may still be operationally unusable if payer enrollment, facility licensing, prescribing, laboratory, pharmacy, or other program requirements do not match the structure. Build a pre-opening checklist that maps legal formation to every enrollment and credentialing process. Use the exact legal name, tax ID, ownership information, and service locations consistently unless the program requires otherwise.

Ownership changes can also trigger notice or re-enrollment duties. The operating agreement and stock-transfer restrictions should therefore require regulatory and payer review before a transfer closes. A buy-sell transaction that is valid under corporate law can still create operational disruption if the practice learns afterward that a payer or license required advance notice.

Use intercompany agreements to document real services

If an MSO leases space, employs nonclinical staff, licenses software, provides billing support, or advances working capital, document those arrangements in written agreements with commercially supportable terms. The agreements should define services, pricing, term, termination, data handling, insurance, intellectual property, and transition obligations. The paper should match what actually happens each month.

Avoid circular arrangements that exist only to move professional revenue. A management fee should correspond to management services. A lease should correspond to real premises or equipment. A trademark license should correspond to actual intellectual property. Good documentation makes the structure easier to explain to lenders, buyers, payers, regulators, accountants, and future owners.

Plan for loss of license and owner transitions

Professional entities need governance provisions ordinary companies can overlook. What happens if an owner dies, retires, becomes disabled, loses a required license, or becomes ineligible to own the entity? The documents should address voting, compensation, repurchase, valuation, temporary transitions, and deadlines for curing ownership problems. Insurance and succession planning should align with those provisions.

Do the same for managers and directors. If a PLLC requires licensed managers for the profession, a vacancy can be more than a governance inconvenience. Maintain a roster of license status and build periodic verification into the compliance calendar. The structure should remain compliant after predictable life events, not only on formation day.

Choose the structure only after a control test

Before filing, run a control test: who owns the practice, who can vote, who appoints managers, who hires clinicians, who sets clinical policy, who controls bank accounts, who bills, who receives professional fees, who signs payer agreements, who controls records, and who can sell the practice. If the answers place professional control with an ineligible person or management company, revise the structure before launch.

A PC, PLLC, and MSO are tools, not labels of quality. The right structure is the one authorized for the profession, aligned with fee and ownership restrictions, workable for tax and financing, and faithful to the business’s real operations.

Entity documents should make that answer visible to someone reviewing the company years later.